讓Scrapy跟隨鏈接並收集數據

Question

我想在Scrapy中編寫程序以打開鏈接並從此標記收集數據：<p class="attrgroup"></p>。

我設法讓Scrapy收集來自給定URL的所有鏈接，但不遵循它們。任何幫助非常感謝。

Answer 1

你需要得到Request實例的鏈接可循，分配一個回調和提取所需p元素的回調文字：

# -*- coding: utf-8 -*- 
import scrapy 


# item class included here 
class DmozItem(scrapy.Item): 
    # define the fields for your item here like: 
    link = scrapy.Field() 
    attr = scrapy.Field() 


class DmozSpider(scrapy.Spider): 
    name = "dmoz" 
    allowed_domains = ["craigslist.org"] 
    start_urls = [ 
    "http://chicago.craigslist.org/search/emd?" 
    ] 

    BASE_URL = 'http://chicago.craigslist.org/' 

    def parse(self, response): 
     links = response.xpath('//a[@class="hdrlnk"]/@href').extract() 
     for link in links: 
      absolute_url = self.BASE_URL + link 
      yield scrapy.Request(absolute_url, callback=self.parse_attr) 

    def parse_attr(self, response): 
     item = DmozItem() 
     item["link"] = response.url 
     item["attr"] = "".join(response.xpath("//p[@class='attrgroup']//text()").extract()) 
     return item